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This paper reports on the methodology and an application of a dialectical approach to research and development, planning. The methodology features a structured debate followed by argumentation analysis. The argumentation analysis in turn is followed by an assessment of the plausibility of the arguments. The application involved using the methodology to assess the level of funding for research and development for a transportation system that would employ advanced technology. The Dialectic Inquiry process, and specifically, the plausibility rating activity, were seen as valuable aids for policy analysis.

Instruments for the Solar Probe mission must be designed not only to address the unique scientific measurement requirements, but must be compatible with the modest resource dollars as well as tight constraints on mass and power. Another unique aspect of the Solar Probe mission is its constraint on telemetry and the fact that the prime science is conducted in a single flyby. The instrument system must be optimized to take advantage of the telemetry and observing time available. JPL, together with industry and university partners, is designing an Integrated Space Physics Instrument (ISPI) which will measure magnetic fields, plasma waves, thermal plasma, energetic particles, dust, and perform EUV/visible and coronal imaging for the Solar Probe mission. ISPI uses a new architecture and incorporates technology which not only eliminates unnecessary duplication of function, but allows sensors to share data and optimize science. The current ISPI design goal (for a flight package) is a 5 kilogram / 10 watt payload.

The far-ultraviolet (FLJV) performance of optical imaging instruments using cooled detectors is extremely sensitive to molecular contamination. Conventionally stringent cleanliness standards for material screening, hardware fabrication, and assembly level test and integration are inadequate for instruments which require a stable FUV performance. A multifaceted contamination control strategy has been developed for the second generation Wide-Field and Planetary Camera (WFPC-2) to improve the FIJV stability by several orders of magnitude, compared to the first camera (WFPC-l). This strategy involves: Improved on-orbit boil-off capability of the detector optics, added internal shielding and instrument venting, in-process subassembly vacuum bakeout at elevated temperatures, material substitution, sample testing in ultra-clean vacuum facility, and internal instrument contamination transport modelling. A science performance goal of 1% photometric accuracy at 1470 Angstrom over an extended time (of at least 30 days) has been established as a contamination control target for WFPC-2. The WFPC-2 is currently planned to be launched by the Shuttle in mid-1993 and replace the WFPC-l which was recently launched with the Hubble Space Telescope (HST).